What is soundstage?

The sense that instruments are coming from some distance beyond the headphone driver. Usually it's divided into a width and depth, and headphones have mostly width unless the recording is binaural (basically, designed for headphones).

That depends on you. There's no agreed upon "neutral" size, because that depends on the recording more than anything.

I'm more of an imaging guy myself. I want to be able to point in a direction and say "That instrument is coming from there." I don't care as much if it sounds like it's coming from a couple inches away or a football field.

To give you a better reference the "better" soundstage sounds closer to a good pair of speakers positioned optimally. 

I think soundstage is a speaker term, since speakers can create holographic sounds, that resemble a stage.

An IEM or HP doesn't really have any of that soundstage, it can't make a holographic piano in front of you, so I call it soundspace instead, I think that's more accurate, that's just me.

Sound Stage is defined (in my own words) as: The ability for a sound system (headphones, speakers, etc) to create the sense, or illusion, that different instruments are placed around you at different angles and different distances.  Essentially, a sound stage allows a user to visualize the location of certain sounds in a given recording.

Terms used with sound stage that describes it:

• Width: Your left to right is the width of the sound stage. 
• Height: Your up and down is the height of the sound stage.
• Forward/backward: Your front and back is this part of the sound stage.

Your in the sound science section, so I'm going to give you my ideas on how it actually works.  Please note that these ideas are 100% accurate, they are just generalizations based on every pair of headphones I've ever put on (from IEMs, to actual headphones, to earbuds).  I believe that it is based on the actual frequency curve of the sound system.  As you know, the way we actually determine distance is through the loudness of something.  So if a certain frequency is softer than another on a pair of headphones, it'll create the illusion that it is further away.  What also seems to follow is that most headphones that have really great sound stage are not neutral or flat (normally are never close to it either). To add, it seems that on just about every headphone that I've heard have sound stage, it almost always had a V/U shaped curve to it.  This allows layering in the mid-range which makes some things sound really close, and some others really far.  Again, this isn't 100% concrete.

If you down-convert stereo to mono there is still a soundstage so it's not just a stereo illusion, obv.

Quote:

Originally Posted by sneaglebob 

I hear people discussing the soundstage of headphones and I dont know what that is. so, what is it?

 

So is it good if headphones have "Above average soundstage"?

The illusion created by stereo speakers that instruments have "place" on the stage i.e. left/right guitar vocals in the middle, drum sets have pieces from the left to the right, all kinds of other effects are mixed in here and there. Only happens in stereo speaker systems. Headphones created head stage, technically but the two are used interchangably.
 

Above average is size? Depth? Width? From the headphones I've heard, it's very difficult to get much depth. Width/Size is good and artificially created on sound headphones like the AKG K70x series. But most of what sound stage is is determined by the recording. Also keep in mind, there no agreed upon normal sound stage. Some people like width, some like depth, some like small sound stage for a more engaging presentation. Tastes are all over the place.

It's not only a stereo illusion though.

It's an unquantifiable subjective term, thats what it is. 

Quote:

Originally Posted by NinjaSquirt 

The illusion created by stereo speakers that instruments have "place" on the stage i.e. left/right guitar vocals in the middle, drum sets have pieces from the left to the right, all kinds of other effects are mixed in here and there. 

Isn't that instrument separation?

Nah, instrument separation is a function of soundstage and clarity